script for setting up MagicAnimate environment with model downloads

[k4l1sh]

I developed this script to simplify the setup of the Python virtual environment and model downloads.

If this PR is accepted, the user just need to run:

wget -q https://raw.githubusercontent.com/magic-research/magic-animate/main/scripts/run.sh
chmod +x run.sh
./run.sh

This will launch the gradio demo with everything installed.

Note: The user needs to ensure that system dependencies are installed.
For Debian-based Linux systems, they can be downloaded with:

sudo apt install wget git python3 python3-venv git-lfs